In Testing for Differences Between the Means of Two Related $H _ { 0 } : \mu _ { D } = 2$

Short Answer

In testing for differences between the means of two related populations, the null hypothesis is a) $H _ { 0 } : \mu _ { D } = 2$ .
b) $H _ { 0 } : \mu _ { D } = 0$ .
c) $H _ { 0 } : \mu _ { D } < 0$ .
d) $H _ { 0 } : \mu _ { D } > 0$ .